汽车车身板用变形铝合金研究进展

基于汽车轻量化的大背景,铝合金因其优异的综合性能成为汽车用板材的优选材料.主要综述了汽车车身板用变形铝合金的研究进展,以汽车车身板材常用的2×××、5×××、6×××和7×××系变形铝合金的应用现状为基础,结合国内外研究者现阶段的研究成果,对各系变形铝合金应用在汽车车身板中的优劣势展开了分析.在此基础上,着重介绍了各系...     

铝合金在汽车上的应用

摘甍作为未来汽车节能环保重要措施的汽车轻量化越来越多的受到研究者的关注,而铝合金作为轻量化材料也得到了很大的关注,本文通过介绍铝合金在汽车上的一些应用介绍。使铝合金材料得到更好的应用与发展,指出铝合金在汽车上应用的重要意义。     

6000系汽车车用铝合金的研究应用进展

综述了6000系铝合金的性能特点以及国内外的研究应用现状,指出了6000系铝合金的发展方向和未来的研究重点,说明了该系铝合金在汽车上具有广泛的应用空间,为汽车用铝合金材料的研究者和汽车的设计者提供了新思路.     

汽车铝合金轮毂的成形工艺

介绍了汽车铝合金轮毂几种主要成形工艺的特点和应用概况,指出随着汽车工业对高质量铝轮毂的需求日益增加,传统的成形工艺正得到不断改进,挤压铸造和半固态模锻等一些新的金属成形工艺也将在汽车铝轮毂生产中得到应用.     

车身制造中的铝合金板热处理-冲压一体化技术

随着能源和环境问题日益严峻,对汽车轻量化的需求愈发强烈,高比强度铝合金板在车身中的应用成为重要发展方向.铝合金板在室温下较低的成形性促使人们将各种成形技术引入到汽车制造领域.本文简述了适用于铝合金板件小批量生产的超塑性成形和板材液压成形等特种成形技术,重点介绍了适用于铝合金构件大批量生产的热处理-冲压一体化技术,包括带中间退火-冲压一体化技术、温冲压、W态下冲压和热冲压,阐明了它们的发展历史和现状,指出铝合金板热处理-冲压一体化技术控形控性的关键,最后比较了不同技术的优缺点,并展望了铝合金板冲压技术未来应重点开展的工作.     

汽车车身轻量化发展方向探讨

系统阐述了汽车车身轻量化设计过程中运用的3种主要方法：在车身结构优化设计方面,详细介绍了拓扑优化、灵敏度分析和形貌及尺寸优化在车身轻量化设计中应用的步骤及方法;在先进工艺应用方面,介绍了激光拼焊板、热冲压成形技术、辊压成形技术的优缺点,以及这些先进工艺应用于车身的位置;在车身新材料应用方面,介绍了高强度钢板、铝合金、塑料及高分子复合材料、静音钢板和结构发泡材料等在车身上的应用及发展情况.以大量实例和统计数据,并通过表征车身轻量化的关键指标——车身轻量化系数验证,得出汽车车身轻量化设计的步骤及发展方向.     

高品质铝合金汽车板预处理气垫炉技术

首先介绍了铝带预处理的原理、工艺特点及气垫炉的工作原理,研究了汽车板生产工艺流程中的难点和重点,指出了气垫炉的工艺位置和不可替代的重要作用;回顾了铝带气垫炉生产线的发展过程,并对其进行了阶段划分和总结;分析了铝带气垫炉的研究现状,对其关键技术进行了深入分析,提出了铝合金汽车板气垫炉技术今后在工艺、设备及控制模型方面的研究重点。随着汽车行业轻量化的快速发展,汽车用铝带气垫炉装备、生产工艺技术的研究与开发必将迎来一个新的发展阶段。     

汽车行业发展对轻质结构部件的需求与展望

随着汽车工业2.0时代的来临,汽车零部件的设计和制造正发生着巨大改变,同时对汽车轻量化的要求也进一步提升。介绍了汽车体系各子系统中主要轻质结构部件的现状和发展情况,从不同轻量化材料类型出发,介绍了各个轻质结构部件中铝合金和镁合金部件的应用情况,同时介绍了汽车轻质结构件材料的需求和研发方向。随后综述了轻质结构部件中主要的成形工艺,介绍了各类成形工艺所适用于生产何种零件,并对提高轻质材料在汽车结构件中的应用进行了展望。     

汽车铝合金轮毂涂装线的工艺及设备简介

介绍了汽车铝合轮毂涂装生产线的涂装工艺和设备,并给出了设备的主要技术参数,此工艺和设备同样也适合行摩托车和铝合金轮毂涂装生产线的应用。     

铝合金板成形性及成形工艺研究现状

介绍了铝合金板材成形过程中影响其成形性能的主要因素,提高铝合金成形性能的先进成形工艺,以及有限元分析技术在铝合金板成形领域应用中的进展.指出开展对高性能铝合金板成形性能的实验研究与成形工艺有限元数值模拟有利于拓宽高性能铝合金板成形件在高技术领域的应用.     

The effect of pre-straining on the mechanical behaviour of self-piercing riveted aluminium alloy sheets

Self-piercing riveting as an alternative joining method to spot-welding has attracted considerable interest from the automotive industry and has been widely used in aluminium intensive vehicles. Pressing and stamping are important processes in automotive production and result in additional straining on the vehicle body sheet material. It is therefore important to have knowledge of the effect of sheet pre-straining on the quality of the self-piercing riveted joints and on the mechanical behaviour of the riveted aluminium alloy sheets. This paper reports the influence of sheet pre-straining on the static and fatigue behaviour of self-piercing riveted aluminium alloy sheet. Wrought aluminium alloy sheet, NG5754 with a nominal thickness value of 2 mm was used to obtain pre-strained NG5754 sheets with pre-straining levels of 3%, 5% and 10%. Pairs of pre-strained NG5754 sheets were joined to create single-riveted lap joints which subsequently underwent lap-shear and fatigue testing. Microscopic inspection showed that the joint quality was satisfactory despite the increasing sheet straining levels. The results showed that by increasing the pre-straining level up to 10%, the shear and fatigue strength also increased. The rate of increase of the static and fatigue strength differed as the pre-straining levels varied.     

Umformbare Al-Werkstoffe – für jede Anwendung

Highly Formable Multi-Purpose Al Alloys Microstructural control through appropriate alloy design and definition of processing schedule, as well as a critical view on the interaction of alloy and forming process, has enabled successful application of aluminium alloy sheet in areas where a good formability is a requirement together with an elevated strength level. Further developments along these lines will promote the introduction of aluminium alloys in new markets where, despite its advantages in terms of weight and corrosion resistance, their penetration has been hindered by only moderate formability.     

铝合金发动机罩内板充液成形工艺研究

目的研究铝合金发动机罩内板充液拉深-局部关键特征刚性整形复合成形工艺。方法在Dynaform中建立有限元模型,优化液室压力及加载路径等关键工艺参数,并进行试验验证。结果液室压力及加载路径对充液成形零件质量的影响较大,成形所需的最大液室压力为10 MPa,并且液室压力不宜加载过早,当凸模行程在30~40 mm之间时,进行合理的液室压力加载可较好地成形该铝合金内板件。结论对于文中研究的大型多特征铝合金发动机罩内板,采用充液拉深-局部关键特征刚性整形复合成形工艺更有利于其成形,可得到合格零件。     

A review on selective laser sintering/melting (SLS/SLM) of aluminium alloy powders: Processing,microstructure, and properties

Manufacturing businesses aiming to deliver their new customised products more quickly and gain more consumer markets for their products will increasingly employ selective laser sintering/melting (SLS/SLM) for fabricating high quality, low cost, repeatable, and reliable aluminium alloy powdered parts for automotive, aerospace, and aircraft applications. However, aluminium powder is known to be uniquely bedevilled with the tenacious surface oxide film which is difficult to avoid during SLS/SLM processing. The tenacity of the surface oxide film inhibits metallurgical bonding across the layers during SLS/SLM processing and this consequently leads to initiation of spheroidisation by Marangoni convection. Due to the paucity of publications on SLS/SLM processing of aluminium alloy powders, we review the current state of research and progress from different perspectives of the SLS/SLM, powder metallurgy (P/M) sintering, and pulsed electric current sintering (PECS) of ferrous, non-ferrous alloys, and composite powders as well as laser welding of aluminium alloys in order to provide a basis for follow-on-research that leads to the development of high productivity, SLS/SLM processing of aluminium alloy powders. Moreover, both P/M sintering and PECS of aluminium alloys are evaluated and related to the SLS process with a view to gaining useful insights especially in the aspects of liquid phase sintering (LPS) of aluminium alloys; application of LPS to SLS process; alloying effect in disrupting the surface oxide film of aluminium alloys; and designing of aluminium alloy suitable for the SLS/SLM process. Thereafter, SLS/SLM parameters, powder properties, and different types of lasers with their effects on the processing and densification of aluminium alloys are considered. The microstructure and metallurgical defects associated with SLS/SLM processed parts are also elucidated by highlighting the mechanism of their formation, the main influencing factors, and the remedial measures. Mechanical properties such as hardness, tensile, and fatigue strength of SLS/SLM processed parts are reported. The final part of this paper summarises findings from this review and outlines the trend for future research in the SLS/SLM processing of aluminium alloy powders.     

A comparison of the mechanical behaviour of self-piercing riveted and resistance spot welded aluminium sheets for the automotive industry

The increased application of lightweight materials, such as aluminium has initiated many investigations into new joining techniques for aluminium alloys. The resistance spot welding (RSW) concept for aluminium has always attracted many researchers from different organizations. Self-piercing riveting (SPR) is the major production process used to join aluminium sheet body structures for the automotive industry. The research team at the University of Warwick has investigated these two major joining technologies for aluminium assembly. The paper reported here gives an in depth comparison of the mechanical behaviour for each joint type under different loading conditions. It covers symmetrical and asymmetrical assembly from thin gauge of 1.0 mm to thick gauge of 3.0 mm. The results suggest that generally RSW can provide similar strength performance to SPR with the exception of T-peel; the energy to maximum load needs be considered ‘case to case’ and is dependent largely on loading conditions and the failure mode particularly with respect to SPR. The spread of results for SPR is generally smaller than for RSW, and the performance of SPR joints improves as the thickness increases.     

Joining of alumina short-fibre reinforced AA6061 alloy to AA6061 alloy and to itself

The weldability of aluminium short-fibre reinforced AA6061 alloy (FRM) to AA6061 alloy and to itself using aluminium brazing materials has been investigated. AA4045 and BA03 were selected as brazing materials. When FRM was brazed to AA6061 alloy with AA4045 sheet, a disorder of fibre orientation near the interface was recognized at a brazing temperature above 863 K. Furthermore, the interface became very irregular and porous. The tensile strength achieved was about 100 MPa on brazing below 863 K. On the other hand, BA03 sheet, which has thin AA4045 layers on an AA3003 alloy layer, made the joint strong. The strength was about 200 MPa. BA03 induced little disorder of fibre arrangement and better contact at the interfaces. The BA03/AA6061 alloy interface was more porous than the FRM/BA03 interface and, hence, weaker. FRM/FRM joints with BA03 sheet had good strengths above 200 MPa.     

Formabilities of steel/aluminium alloy laminated composite sheets

The tensile properties and press formabilities of laminates experimentally produced from mild steel and various aluminium alloy sheets are examined. The tensile properties of the laminates are approximately predictable by the mixture rule of the properties of the individual sheets. The forming limits in deep drawing, as well as stretch forming due to various types of fractures of the laminated composite sheets, cannot be predicted without considering the stress and strain histories of the individual sheets during forming. Furthermore, it is found that the drawability, as well as the stretch formability, is improved by setting the mild steel sheet on the punch side for the case of aluminium alloy sheet with comparatively high ductility, and by sandwiching the aluminium alloy sheet with the mild steel sheets for the case of low ductility.     

AZ80 and ZC71/SiC/12p closed die forgings for automotive applications: technical and economic assessment of possible mass production

Abstract

In this study, redesigning for equal functional properties and rapid prototyping of hot forged automotive parts based on commercially available wrought magnesium alloys (AZ80) and composites (AZ80/SiC/12p) were performed. To achieve the same functional properties in a forged automotive component irrespective of the structural material selected, an automotive connecting rod, mass produced in aluminium alloy 6061, was redesigned to use wrought magnesium alloy (AZ80A) and particle reinforced magnesium alloy matrix composite (ZC71/SiC/12p). By applying conventional hot forging technology, prototype connecting rods were forged, trimmed, and heat-treated on a semiindustrial scale. The microstructure of both as extruded and hot forged specimens was examined and the tensile properties of AZ80, ZC71/SiC/12p, 6061 and 6061/SiC/15p test bars machined from hot forged connecting rods were measured. Weight reduction in the redesigned connecting rods was determined and the substitution of magnesium and aluminium based materials for steel was compared in terms of cost.